Finding out where SharePoint email alias is used

Recently, a question came up in the SharePoint TechNet forums regarding document libraries with incoming email enabled. If you only know the name of the AD contact for the library, how can you find out which document library or list it’s pointing to?

Here’s a straightforward PowerShell script which will iterate through every site collection in every web application and return the names and email aliases of every list that has an active email alias specified.